The invention relates generally to a device for sampling particles from the exhaust gases of a self-igniting internal combustion engine and more particularly to such a device wherein a plurality of test cylinders are employed.
The literature reference "SAE Paper No. 77 08 18, 1977, pages 207-225" discloses a device of the general type for taking samples of particles from the exhaust gases of a self-igniting internal combustion engine for an automotive vehicle drive onto a roller-type test stand The exhaust gases enter into a distributor arranged vertically on the dilution tunnel and flow therefrom through exhaust gas conduits to the filter cylinders. The exhaust gas conduits and the filter cylinders are disposed to emanate in stellar arrangement from the distributor. Consequently, the installation occupies a relatively large space. The filter units are removed from the horizontally disposed filter cylinders in an axial direction. This arrangement requires, in this direction, additional space on all sides for the mounting and dismounting, respectively, of the filter cylinders. This literature reference fails to disclose any information regarding the type of control provided for the individual filter cylinders.
It is one object of the present invention to provide a sampling device of the general type described above which has a compact size.
It is another object of the present invention to provide a sampling device which requires only a small amount of space for changing the filter units.
It is still another object of the present invention to provide a sampling device which allows optimum control of filter units disposed in the device.
These and other objects of the present invention are achieved by the provision of a compact device for sampling particles from the exhaust gases of an internal combustion engine for an automotive vehicle. This device includes a dilution tunnel, to which is supplied all the exhaust gases of the internal combustion engine. From the dilution tunnel, by way of an exhaust gas distributor, a sample stream of exhaust gas is distributed to filter cylinders arranged in exhaust gas conduits, in dependence on the operation of the internal combustion engine. Filter units, traversed by the sample stream of exhaust gas, are removably disposed in the filter cylinders which are vertically arranged and exhibit a filter mounting element accommodating the filter units. This filter mounting element is adapted to be swung out laterally from the filter cylinders after opening of a locking device. A plurality of filter cylinders are provided, each being associated with a specific operating phase of the internal combustion engine, and utilized for determination of the quantity of emitted particles. A filter cylinder designed as a static cylinder is also provided. Upstream and downstream of each filter cylinder, valves are arranged which are adapted to control the flow of the exhaust gas through the individual cylinders.
In the device of the present invention as described above, particle sampling is advantageously possible while the sample stream of exhaust gas flows continuously through the device. Due to the vertically disposed arrangement of the filter cylinders and the design enabling the swinging out of the central filter mounting elements laterally, changing of the filter units can be effected in an extremely small space. Due to the spatial orientation of the exhaust gas distributor and the nonreturn valves with respect to the filter cylinders, the device occupies a minimal amount of space.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.